JEE Main 2019 — Rotational Motion Question with Solution
From: JEE Main 2019 (Online) 12th January Evening Slot
Question
A particle of mass 20 g is released with an initial velocity 5 m/s along the curve from the point A, as shown in the figure. The point A is at height h from point B. The particle slides along the frictionless surface. when the particle reaches point b, its angular momentum about O will be :
(Take g = 10 m/s2)

(Take g = 10 m/s2)

This question includes a diagram. The text above accompanies the figure.
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Show full solutionCorrect option: A
Correct answer
A6 kg-m2/s
Step-by-step explanation
Work Energy Theorem from A to B
Mgh = mv mv
2gh =
2 10 10 = v 52
vB = 15m/s
Angular momentum about 0
L0 = mvr
= 20 103 20
L0 = 6 kg.m2/s
Mgh = mv mv
2gh =
2 10 10 = v 52
vB = 15m/s
Angular momentum about 0
L0 = mvr
= 20 103 20
L0 = 6 kg.m2/s
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